Laminated films are known which are each provided with a thin film layer formed (laminated) on the surface of a substrate in order to impart functionality to a film-like substrate. For example, laminated films having gas barrier characteristics imparted by the formation of a thin film layer on a plastic film are suitable to the filling and packaging of products such as foods and drinks, cosmetics, and detergents. Plastic film substrates have been recently adopted in the fields of liquid crystal displays and organic EL elements to eliminate the drawbacks of glass substrates which are heavy, hard, and fragile. However, these plastic film substrates are inferior in gas barrier characteristics to glass substrates and there is therefore the case where steam penetrates into a device to cause display defects when the plastic film substrates are used in liquid crystal displays.
Methods for forming a thin film of an inorganic oxide on one surface of a substrate film such as a plastic film are being enthusiastically performed to solve this problem. Also, Patent Document 1 discloses a laminated film obtained by forming an organic layer containing, as its major component, an acrylate having a glass transition temperature of 10° C. (Comparative Example 2) to −68° C. (Example 4) on the surface of a substrate film and then by laminating an inorganic layer of silicon oxide (SiO) on the surface of the organic layer. It is reported that when such a structure is adopted, a laminated film can be provided which is resistant to deterioration in gas barrier characteristics even under high temperature and low temperature environments alternately repeated (90° C.-20 minutes and 40° C.-20 minutes).